Tens of thousands flocked to the Empire Polo Club, the site of the already successful Coachella Valley Music and Arts Festival and the Stagecoach Country Music Festival, to witness heavy metal history as The Big 4--Metallica, Slayer, Megadeth and Anthrax--played their first show on U.S. soil Saturday night.

The Big 4 Festival in Indio, CA featured Anthrax, Megadeth, Slayer, and Metallica all in one day at the Empire Polo Field on April 23, 2011.

Metallica -- a band that has sold upward of 60 million albums in the U.S. alone, played 1,697 tour dates around the world and has made metal music heavy enough to melt faces -- has been taking baby steps when it comes to one of the biggest musical events in heavy music.

The rise and rise of Metallica into one of the major forces in rock has unfolded over the decades like a brilliantly executed surprise attack.

Slash, Korn, Slayer, Slipknot, Anthrax, Hollywood Undead, Asking Alexandria, Five Finger Death Punch, Michelle Rodriguez and More Talk When They Discovered Metallica

Kirk Hammett talks about life and his new book on "That Metal Show."

Film explores effects of absent dads

Metallica frontman James Hetfield is tackling a surprising topic in the new award-winning documentary, Absent: fatherhood.